130 Scientific Intelligence. 
these vesicles will form a cloud in the water of the tube, which 
slowly rises and destroys the transparency. 
1. Duprez was good enough to make the experiment at my re- 
quest. The water was suspended in a glass tube of 13 millims. in- 
ternal diameter. A small metal vensel with an aperture of several 
was observed in the water of the tube. The vapor condensed on 
the outside of the tube, and from time to time was wiped away ; 
but the water inside retained all its transparency. 
After this it seems difficult to retain any doubt as to the non- 
existence of the vesicular state. It seems to me, in fact, that only 
“as the first of Pet assumptions must be rejected; for the 
r had previously been eke with air so long as to be com- 
sletet saturated, and, secondly, while it was exposed to the 
~— of va a it must have lost whatever solvent power it pos- 
sed; and, ver, sometimes even comparatively large air- 
hokey eats on 5 the upper part of the inside of the tube, where 
the hotter part of the water ascends. 
e second supposition, though not quite inadmissible, is at any 
rate not very probable. We have seen that our small nt com 
make must be so thick that they are colorless ; otherwise a 
cloud irradiated by the sun could have no bright luster ; fos 
over, from the long duration of large clouds, they must be very 
permanent, 
As regards = Serene is it probable that all vesicles 
eould roll alon su without touching? Moreover pe 
selves in contact with the fluid surface : but nothing in the result 
was different ; no cloud disturbed the transparency of the water. 
